Vortec v6 conversion

[Scott Danforth]

I’m replacing my 4.3 non balanced early 90s motor with a 99 vortec 4.3. I have rebuilt the short block right now but My question I have is since the vortec I have didn’t come with a flywheel will the one from the non balance shaft motor work or since the motor is internally balanced will it not work? And since it has a plastic timing cover will the same 6.75” harmonic balancer Work or is it too big? I held it up and it looks pretty big and the factory balancer looks to be a hair over 6” but won’t work because it’s not flush on the outside to where I can mount my marine pulley on it. Also will the same water pump work? Thanks.

your problem lies in the fact that your trying to use an early set of pulleys with a later motor. the 4.3 went thru 2 major changes and about 3 minor ones between your early 90's and late 90's motor. either switch all the accessories to late model serpentine that is correct for your 96-00 vintage motor or start making custom spacers for your pulleys. a stamped SBC lower pulley for a SWP may work

can you make it work, yes, however you will need to be creative. is it worth the headache, probably not.

the 4.3 damper for your '99 should be 6.140" in diameter. (look at the blaser/bravada/jimmy)

Pioneer DA-1736 or Delco 10224885

 

[77searay197]

Well i put my original boat balancer on, the crank pulley, and waterpump on and the pulleys lined up so I don’t see why the rest of them won’t work

 

[chartersj]

It may bolt up and line up but you might end up with vibration...I used my old damper when I did the swap but my original 4.3 was a balance shaft motor. I have seen others that used the newer style damper that came on a vortec but you need to have the outer lip lathed down so the original v belt pulley will bolt up flush. My original engine circulating pump would not clear the plastic timing cover bolts either.

 

[Scott Danforth]

Well i put my original boat balancer on, the crank pulley, and waterpump on and the pulleys lined up so I don’t see why the rest of them won’t work

you cant put a non-balance shaft damper on a balance shaft motor and not have the motor tear itself apart

 

[77searay197]

What’s the the difference? Arent they both balanced the same? If that was the case wouldn’t I have to change the flywheel too? Whats the diff between a 888776t mercruiser vortec balancer and a pb1200n balancer That u can get at oreillys? They look pretty much identical